Alcator C-Mod Run 1060210 Information

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Miniproposals
Miniproposal:298a
Date Filed: 5/20/2002
Title:C-Mod Plasma Startup
First Author:Jim Irby
Session Leader:Jim Irby (shots 2-17)

Operators
Session leader(s):Jim Irby
Physics operator(s):Steve Wolfe
Engineering operator(s):Andy Pfeiffer,Ed Fitzgerald,Bill Parkin

Engineering Operator Run Comment
MP298A Plasma startup Session leader: Irby,Parker?,Wukitch? Physics oper

Session Leader Plans

Physics Operators Plans
Entered: Feb 9 2006 06:20:52:050PM
Author: Steve Wolfe
Engineering setup for Thursday 9 February 2006

MP298A Plasma startup

Session leader: Irby,Parker?,Wukitch?
Physics operator: Wolfe

Overnight ECDC in D2, and bake at 60 C.

Run begins at 09:00 and ends at 17:00

Power systems as on 1060209001 (0.8 MA, 5.4 T, lower single null)

A-coil configuration: normal [+Dtop -Dbot -Jtop +Jbot] and enabled.

Gas Setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar + 2psi Neon Hybrid DISABLED (PG1)
leave B-side upper as is Hybrid DISABLED (PG2)
fill B-main (C-side) with 40 psi D2 Hybrid enabled (PG3)
leave NINJA as is Leave DISABLED

Enable the following gate valves, assuming no vacuum problems:
ECE, VUV

Torvac setup: Gate valves open

Run plan: Start from 1060209013. Provide target for LH and/or ICRF. 
Shot rate is expected to be extremely low due to poor cooling of 
C-Right Vertical TF leg. We'll do what we can, with the main aim of
getting RF systems some conditioning time and diagnostics checked out
and operational. Some marginal reduction of H/D and other dirt may be
accomplished, depending on how many shots we actually get. It would also
be good to get to use density feedback, if the TCI signal to the control
system can be restored. 



Session Leader Summaries

Physics Operator Summaries
Entered: Feb 10 2006 05:24:41:393PM
Author: Steve Wolfe
Physop Summary for 1060210

MP298a: C-Mod Startup
Also LH conditioning
SL?
PO: wolfe

Not a bad run considering the slow cycle due to the 
poor cooling of the C-right vertical TF leg. The main
purpose today was to get LH power into plasma. This was 
accomplished. Up to 40kW (source) per klystron from 5
tubes was coupled, with no obvious effect on anything. 
All plasmas today were 800kA, LSN, nl04<9e19. 

Brian exercised the scanning probes on several shots. 
We had a few shots with Ar and Ne puffs for John and 
Alex, but this puff was discontinued after a poloidal 
detachment disruption on shot#12 (which may have been
unrelated). 

We had small injections on most shots. Matt says many 
of these were spectroscopically identified as containing
Fe. The injections were also observed on the F-side
video.  At most one seemed to come from the vicinity 
of the LH launcher. 

TCI feedback is still not connected to the interface room,
so we ran with pre-programmed gas all day. The results
may be of some interest with respect to wall-pumping
issues. The puff was unchanged after shot 5. This gave a 
rather consistent nl04=8.5e19 until the detachment/disruption 
event on shot 12. On the next plasma (14), the same puff
only gave 6e19, and subsequent shots only got up to 7.5e19
or so. 

H/D was around .25. Little or no improvement in H/D was 
observed over the run day. 

At one point I loaded in an NL_ZMETER wire, but never enabled it. 

The other main activity today was assessment of the cooling
of the C-right turn. We started the run with the vessel 
setpoints at 20C (instead of the standard 35), and got a consistent
28minute cooldown from -152C after full length 5.4T plasmas to 
-160C. The forced heating of the C-side stub heaters to 60C was also 
turned off before the start of the run, and likely contributed to 
the improved cooldown relative to yesterday, when it was taking 
about an hour. 

The setpoint was then lowered to 10C, which reduced the 
cooldown time to 24minutes. Further lowering the setpoint to 
0C did not result in improved cooldown times, and the setpoint
was returned to 10C for the last couple of shots.  

The Cryo system is being left in SLEEP mode over the weekend,
and a borescope inspection of the C-right cooling connection
will be attempted on Monday. 

Scorecard:

      Tests         1 (Shot1=TF scanner before run)
      Duds          1
      Fizzles       2
      Plasmas      13 (one early disruption, rest full length)
      =========    ==
      Total        17


Session Leader Comments

Physics Operator Comments
Feb 10 2006 07:14:43:777AMSteve Wolfe
Starting from last shot of yesterday:
PG4=23msec
Br0=-.0002
EF4=-1345
NL04 off in seg2; PG3 at 30V [.1,.5]sec

Load at 10-Feb-2006 07:12:01.00
Open tree /home/wolfe/pcs_scratch      -1
Open tree done


Feb 10 2006 07:31:42:550AMSteve Wolfe
C-right vertical came up to -135C overnight,
despite the verticals having been left set
at -165. 

When Andy tried to start the cycle around 7:15
he got the "Do you want to restart servers" message
I noticed that after I logged in as physop the logbook
changed the current run from 1060209 to 1060210. This
is probably just because the logbook is looking at the
max(runs) and the cycle probably doesn't query the same
database, but I'll mention it to Josh when Andy calls him
at 10:30. 


Feb 10 2006 09:26:56:070AM1060210001Steve Wolfe
Shot#1:
C-right vert is still only down to -150. We will 
take a cycle test to get scanner reading. 




Feb 10 2006 10:01:08:913AM1060210002Steve Wolfe
Shot#2: We will try for plasma. 
The vessel temp has been set to 20C for today. 
Willy will take the force off the C-stub heaters
We may get leaks, but we need to assess the C-right
cooling situation today, before we definitely decide to warm up
to fix it. 

LH tree set /include for this shot. 
plasma full length. 
Some runaways early. One bounce, early breakdown.

Temp goes to -152 after pulse



Feb 10 2006 10:21:55:157AM1060210003Steve Wolfe
Shot#3: Raise maintenance level on pg3 in
seg2 from 30V to 35V
pg4 from 23 to 25ms
plasma full length
Still have hards, nl04 at 5 to 6e19
Startup still a little bouncy. 

C-right Temp from -161 before to -153 after.  
next shot: raise pg4 again

Feb 10 2006 10:33:48:213AM1060210003Steve Wolfe
Shot#4: pg4 from 25 to 27ms
There will be a cell access for the lower hybrid
to move the launcher forward. 

Feb 10 2006 11:15:26:527AM1060210004Steve Wolfe
Shot#4: pg4 from 25 to 27ms
There will be a cell access for the lower hybrid
to move the launcher forward. 
While I'm waiting, load wire 14 with nl_zmeter from
shot 1051130015 wire 11, turn its gain from 4 to zero
Load it so I can see the aout
plasma full length. No bounce, no hards.

Temp down to -163 after 48minutes (mostly at 3psi)
-164 before shot; -156 after.

Feb 10 2006 11:31:57:677AM1060210005Steve Wolfe
Shot#5: Increase PG3 to 50 between .1 and .5sec, 15V to 1sec
Enable argon/neon puff. 
Lots of runaways, plasma full length. 

temp at -152 after (didn't notice before)
next: raise pg4 again

Feb 10 2006 11:59:59:430AM1060210006Steve Wolfe
Shot#6: pg4 to 30msec
plasma full length. No hards
nl04 nice and flat at 8e19; I'll leave nl_zmeter
off until there seems to be some reason to use it. 

25 minutes to get to -160C; -152 after shot

Feb 10 2006 12:14:10:973PM1060210006Steve Wolfe
Shot#7: No changes
Launcher may have been further in than thought.
Cell access to move it back out a few mm.



Feb 10 2006 12:31:22:263PM1060210007Steve Wolfe
Shot#7: No changes
Launcher may have been further in than thought.
Cell access to move it back out by 5mm.
plasma full length; breakdown a bit later,
no runaways. nl04=8.5e19

about 30 minutes to get to -160C; -152 after shot
next shot: no changes

Feb 10 2006 01:02:25:157PM1060210008Steve Wolfe
Shot#8: no changes
LH timing moved from 0.3 to 0.7sec
PG1 puff increased from 30 to 40msec
plasma full length, no runaways
No obvious effect of LH on plasma at 0.7sec

28min to -160C; -152 after pulse

Feb 10 2006 01:32:35:380PM1060210009Steve Wolfe
Shot#9: no changes
Brian will start scanning the probes this shot
fizzle. Irby jinxed it. 

28min to -160C; -154 after
next: 5A negative on ef4

Feb 10 2006 01:55:10:283PM1060210010Steve Wolfe
Shot#10: ef4 from -1345 to -1350;pg4 from 30 to 29ms
Changing vessel temp set points from 20C to 10C
plasma full length, 3pokes by Brian
no runaways (maybe one tiny dump)
nl04=8.4e19
No LH this shot, because they are looking into why 
they weren't stopped by the fizzle detector last shot.

19min to -160; -152C after shot


Feb 10 2006 02:21:39:807PM1060210011Steve Wolfe
Shot#11: Increase pg1 puff from 41 to 50msec
plasma full length. Breakdown a little later
no runaways

24 min to -160C;-152 after 

Feb 10 2006 03:00:18:183PM1060210012Steve Wolfe
Shot#12: No changes
plasma disrupted early (.6sec)
density took off? Gas puff is the same as 11?
Pressure is rising but gas looks normal.
Looks like a poloidal detachment.
Argon turned off for next shot. 

Next shot: vessel set down to 0C 
(despite fear that this could have had 
something to do with this shot's problem).

25 min to -160C; -153 after

Feb 10 2006 03:15:19:833PM1060210013Steve Wolfe
Shot#13: No changes 
(other than argon off and vessel temp)
fizzle, should have dropped pg4 probably.
 Shot 1060210013: \mag_bp_coils.signals:bp01_bc            has a baseline offse
t     -1.1E-02

22 min to -160C; -155 after

next shot: drop pg4 2msec

Feb 10 2006 03:45:22:917PM1060210014Steve Wolfe
Shot#14: drop pg4 from 29 to 27ms
Brian is stopping probes for now.
plasma full length. No runaways.
nl04=6e19 with same gas puff. 

18 min to -160C;-152 after pulse

Feb 10 2006 04:04:08:110PM1060210015Steve Wolfe
Shot#15: No change. LH will try to fire this time.
plasma full length. No runaways.
nl04=7.4e19

24 min to -160; -152 after shot. 

Feb 10 2006 04:31:53:663PM1060210016Steve Wolfe
Shot#16: pg4 from 27 to 26ms
Brock will fire a Li pellet at 1.4sec
Vessel setpoint is back to 10C
Dud! shouldn't have dropped it I guess.

24 min to -160C; -154 after
next shot: up to 28msec on pg4

Feb 10 2006 04:54:27:750PM1060210017Steve Wolfe
Shot#17: pg4 from 26ms to 28ms
Brock will fire a Li pellet at 1.4sec
Vessel setpoint is back to 10C
plasma full length.
nl04=7.7e19, no runaways.
LPI gate valve didn't open.

17 minutes to -160; -152 after shot.
END OF RUN.


Engineering Operator Comments
ShotTimeTypeStatusComment
109:27:40:287AMTestOk
209:56:10:230AMPlasmaOk
310:18:27:407AMPlasmaOk
411:12:33:013AMPlasmaOk
511:27:06:600AMPlasmaOk
611:55:23:480AMPlasmaOk
712:27:13:013PMPlasmaOk
812:58:09:720PMPlasmaOk
901:29:18:397PMPlasmaOk
1001:50:41:550PMPlasmaOk
1102:17:46:463PMPlasmaOk
1202:46:21:953PMPlasmaOk
1303:10:51:913PMPlasmaOk
1403:31:27:110PMPlasmaOk
1504:00:38:003PMPlasmaOk
1604:27:57:350PMPlasmaOk
1704:47:26:953PMPlasmaOk